Training and recovery behaviors of exchange bias in FeNi/Cu/Co/FeMn spin valves at high field sweep rates

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:324

Article

Yang, D. Z.^1,2  Kapelrud, A.¹  Saxegaard, M.¹  Wahlstrom, E.¹ 

[1] NTNU, Inst Fysikk, NO-7491 Trondheim, Norway

[2] Lanzhou Univ, Key Lab Magnetism & Magnet Mat, Minist Educ, Lanzhou 730000, Peoples R China

关键词: Antiferromagnet;    Exchange bias;    Training effect;   

DOI  :  10.1016/j.jmmm.2012.05.002

来源: Elsevier

【 摘 要 】

Training and recovery of exchange bias in FeNi/Cu/Co/FeMn spin valves have been studied by magnetoresistance curves with field sweep rates from 1000 to 4800 Oe/s. It is found that training and recovery of exchange field are proportional to the logarithm of the training cycles and recovery time, respectively. These behaviors are explained within the model based on thermal activation. For the field sweep rates of 1000, 2000 and 4000 Oe/s, the relaxation time of antiferromagnet spins are 61.4, 27.6, and 11.5 in the unit of ms, respectively, much shorter than the long relaxation time (similar to 10(2) s) in conventional magnetometry measurements. (C) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

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